Electric connecter plug



Oct. 11, 1938. H. D, EY ER 2,132,870

ELECTRIC CONNECTER PLUG Filed Nov. 29, 1935 mvzu'ron Harv 2 Gavel .7 MBY HIS ATTORNEYS Patented Oct. 11, 1938 UNITED STATES ELECTRIC CONNECTED- PLUG Harvey D. Geyer, Dayton; Ohio, assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Application November 29, 1935, Serial No. 52,172 2 Claims. (01. 173-361) This inventionrelates to electric connecter plugs such as are used to connect electric extension cords to convenience outlets or other electric receptacles.

An object of this invention is to provide a connecter plug which is substantially unbreakable, easy to attach to the end of an electric cord or insulated wire and at the same time gives a firm anchorage of the cord to the connecter plug so as to take the strain off theconnectionof the cord to the contact prongs, and which is emcient and durable in use, neat in appearance, and economical to make and assemble.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accomsembled plug.

2 is an end view taken along arrow 2 of Fi Fig. 3 is a plan viewof Fig. 1..

Fig. 4 is an end view taken along arrow 4' of Fig. 3.

Fig. 5 is a section taken on line 55 of Fig. 3.

Fig. 6 is a cross section taken on line H of Fig. 5 and showshow the two wires of the cord are connected to the two contact prongs.

Figs. '7, 8 and 9 show a modified form of the invention wherein the electric cord extends at right angles to the contact prongs.

Fig. 7 is a side elevation of the plug.

Fig. 8 is a section taken on line 8-8 of Fig '7.

Fig; 9 is a section taken on line 9-9 of Fig. '7.

Similar reference characters refer to similar parts throughout the several 'views.

Referring to Figs. 1 to 6, the connecter plug comprises a main body 10, molded in one piece from semi-soft or resilient rubber so that it will not crack due to a sharp blow as when it is let fall upon .a hard floor. This main body it has an elongated handle portion II and a preferably enlarged head portion 12 which serves to retain the metal contact prongs l3 in the proper spaced location. Head portion l2 has an annular molded groove or recess 15 therein which is preferably open to the outside lateral surface of the main body 10 all around its periphery; A second molded recess l6 extends axially thru the handle portion H and is of such size as to snugly,

l6 communicates with the annular groove l5 thru a diametral transverse recess I! (see Fig. 6) which is preferably of sufficient size to permit access to the inner end of the cord ll after it has been pulled into proper place into its recess 5 l8 and thus enable a-knot 20 to be tied in the two insulated wires 2| and 22 contained in the cord it (see Fig. 5). In order to tie the knot 20 more conveniently, the cord Il may be pulled thru its recess 16 and out laterally thru recess 10 I] so that its end projects far enough out of groove I 5 to conveniently tie a suitable knot 20 r in wires 21, 22, after which cord 14 may be pulled back until the knot 20 is located at the center of the transverse recess I! as shown in 15 Fig. 5. Or if desired the rubber head portion ,I2 may be slit diametrically across at 23 after it is molded, so that said slit 23 may be opened temporarily sufliciently to pull the cord out thru slit 23 to more conveniently tie the knot 20 there- 20 matter which cord I4 is pulled back in place as shown in, Fig. 5. This knot 20 is somewhat larger than the main portion of cord I4 and hence aids materially in anchoring cord M in the rubber connecter plug.

The two metal' contact prongs l3 may be molded in place as inserts, but preferably they are not so molded in place but are separately snugly inserted in correspondingly shaped moldedrecesses 25 in the soft rubber body Ill. Contact prongs l3 preferably are,each formed with an angle 26 at its inner end to provide more endwise bearing surface to better hold it in its proper location. After prongs 13 are properly inserted in place, the ends of the two wires 2| and 22 arepassed out of opposite ends of transverse recess l1 and individually electrically connected to the two prongs 13 by binding screws 21, this being easily done since at this time the molded annular groove 15 is still uncovered by the sep 40 arate closure ring 30 which will now be described.

This closure ring 30 is shown in the drawing 'as an elastic rubber ring or annulus which is snapped into place to completely cover the groove 45 i 5 after "the wires 2| and 22 are connected to the contact prongs I3 and provide a neat appearance to the connecter plug. Ring 30 is better retained in place by the molded shoulders on the rubber main body Hi. If the slit 23 has 50 been provided in body III as above described, ring 30 will also serve to'hold this slit 23 tightly closed. If desired, this ring 30 may be o metal or other non-stretchable material since the soft rubber retaining shoulders on body l0 may be 55 made sufiiciently distortable to permit a nonexpansible closure ring to be pushed into place as the final step of assembling.

Figs. 7, 8, and 9 show a' form of the invention wherein the; electric cord IQ extends at right angies to the contact prongs i3. This form is siinflar to that described above except that,;the handle portion 3-! thru which the cord M Vextends is formed integral with the flexible rubber closure ring" 30 rather than integral with the main body ill for obvious reasons; In assembling this form, the cord I4 is first threaded thru hole 32 and'out thrii one end of closure ring 30 sumciently iar to permit theknot 20 to be. tied in wires 2| and 22 and the ends of these wires to be properly connected to the contact prengs I3 after they have been inserted to proper position in the main body It. The closure ring 30' is then slipped along cord it until the knot 20 abuts the inner end of the handle portion 3! and in the meantime the annular portion of ring 30" is distorted and snapped over one end of the main body it so that it will completely close the -open groove i5 as clearly shown in Fig. 8, This laterally open groove I5 serves the same purpose in this form as in the first form, namely, to'provide ready access to both the inner ends of the wires and the inner ends of thecontact prongs so as to permit theconnection of these parts after they have been separately inserted into the main body of the connecter.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form,

it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows: 1. An electric push-in plug attached to the end of a flexible electric cord, said plug comto aid insertion efsaid cord, said rubber body,

having a moldediperipheral opening permitting access to the inner ends of both of said prongs i and the fiexible cord after insertion in said body whereby said cord may be properly connected to said prongs, and a separate elastic closure ring for said peripheral opening snapped in place after said cord has been connected to said prongs and holding said slit nofinally closed.

2. An electric push-in' plug attached to the end of a flexible electric cord, said plug comprising two metal contact prongs, a one piece resilientglrubber main body having two spaced gecesses into which said two prongs are snugly inserted and a second recess communicating with the inner ends of said prongs 'into which the flexible cord is snugly inserted; the portion of said resilient body oppsite said second recess having a normally closed slit therein which may be temporarily c-pened by fiexure of the rubber body to aid insertion of said cord, sa'idrubber body-having a molded lateral opening of substantial size permitting access to the inner ends of said two prongs and cord after insertion in said body whereby the individual wires of said cord may be connected to said prongs, and a separate ring-like closure member surrounding the slitted portion of said body and covering said lateral opening! g HARVEY D. GEYER. 

